g0ozs

Well done both - I hope to meet you on air before too long ! I can put a RT353 or 320 on air at short notice if you are within 50 miles and want to try 4m or 6m.

As an aside the Felixstowe & District ARS has a course next weekend which is I think fully booked - if anyone in Suffolk or N. Essex is interested I can put you in touch for next time which will be in the spring.

Iain

73 de G0OZS

(Manningtree, Essex)

AlienFTM

The precursor was the A43R - the one with 6 xtal controlled channels that had positive earth so care had to be taken in vehicle installations to insulate the case!

http://www.wftw.nl/larkspur/a43r.jpg

Regards

Iain

73 de G0OZS (a happy RT321 user to this day)

Ian, Alien

A folded dipole is effectively two half wave dipoles connected at the ends in parallel (the join opposite the feedpoint is a low voltage/high current point being short circuit in many designs) so the wavelength in this case will be 9 to 20 feet = 3 to 6 metres - so VHF combat net radio of some kind rather than HF I think.

Regards

Iain

Ian

It would be useful to get some idea as to the size of the antenna and where it came from - this will at least determine the range of possible sets based on the operating frequency. If it is around 2 metres long it will have been used with one of the combat net radios (A41/42, C42/45 or B47/48) in the Larkspur era and if it is short - less than a metre - it will have been used with a UHF air to ground set - either a mobile A43 or the ground based setups a Collins AN/ARC52 (aka PTR175 or Station Radio C48) that was used in landrover ground to air setups during the 1960s. It wasn't the original ASSU configuration with BE601 UHF, because that is specified as using a vertical rod antenna.

Regards

Iain

Mark

I should have added - the Lamp / Call button lights the dial lamps in one position and sends a call tone to the remote handset in the other position (when a handset is connected and the radio is in IC or REM mode)

The CRL/R box should not be necessary with this radio as there are terminal posts on the side for D10 cable connections, similar to those on a 351/2.

Regards

Iain

Hi

The mode switch settings are as follows:

LOCAL Use with normal Clansman headset and microphone

Mute O/R Overrride receive squelch to listen for weak signals

REM Remote operation with handset or remote combining unit over D10 field telephone cable

AUTO Re-Broadcast (when linked to remote terminals of another radio e.g. RT351/2 or 353)

IC Intercom (between RT344 headset and remote handset connected over D10)

BEACON Continuous transmit for use as a beacon that aircraft can home on to

Please note that the 344 operates in the Military Aircraft UHF band (from memory, without retrieving mine from storage to check) from 250 to 500MHz by 50KHz steps), and there is no amateur band in this range. So transmitting use is not possible in the UK - it may be of use as a receiver at air shows however.

Regards

Iain

Hi Marmon

Thanks for this! It is good to know there are still SUMBs available and some of these look to be in better condition than mine (which spent most of the last 20 years on a farm). I haven't had the greatest success getting spares in the UK for mine (I do know about RR services in Kent but they didnt always have what I needed when I needed it!) and would be interested in contact details for anyone in France who is able to supply either new old stock or recovered parts. I'm particularly interested in NOS fan belts, a fuel pump and the rubber seal for the fuel filter at the moment.

Regards

Iain

Hi Again

I went out to the shed and looked at some antenna bases this weekend. The VHF base used with the TUAAM is actually in two parts - the wire ended Base Antenna Mounting No.31 MK 6 and the Base, Antenna Element Mk 2 which is the cylindrical part below the rubber.

Base Antenna Mounting No.31 Mk 2 is the part with a wire connection and can be used without the Base Antenna Element for HF with a 321 or 320 - just fit 4 metres of antenna elements and connect to the wire antenna terminal of a 320 or a 321 TURF. You should also connect a counterpoise wire of approximately 1/4 wavelength at the frequency in use to the earth terminal of the radio or TURF and lay that along the ground for best results - failing that connect the earth to the vehicle body.

Base Antenna Element Mk II contains a small (surprisingly small - about 1cm cube) transformer with input from the BNC connector and output to the base No.31 Mk 6 and is I think specifically designed for use with the TUAAM and VHF antennas of 2 metres length. This is of interest to me because I would like to make my radio SUMB look original with jeep-style MP65 ceramic antenna bases from the outside while having a Clansman radio fit inside, but the lack of a transformer in the MP65 base (which is electrically the same as a bare No.31 Mk6 base) may mean I can't use a TUUAM directly - I need to make an equivalent of the transformer in the Base Antenna Element Mk II first.

Regards

Iain

Hi

Regarding the 320 the socket with black plastic surround (and the push down connector) are the antenna connections for the manpack whip and wire antennas respectively. The knurled knob is the earth connection.

The connections for a 321 and 353 in vehicles are respectively

321 - coax - SURF (optional) - TURF - single wire feeder - HF antenna base

353 - coax & 12-pin cables - ARFAT - coax & 7 pin cable - TUUAM - coax - VHF antenna base

The TUUAM is an automatic VHF ATU (so a fixed length antenna outside the vehicle can be used on any frequency between 30 and 80 MHz without going outside to adjust it!). They are used with the RT353 in conjunction with an ARFAT (which reduces transmitter power until the TUUAM has matched the antenna) and with the RT351/2 sets in conjunction with an Initiate box that manually keys the radio and starts the tuner at the same time.

TURF is a manual ATU (with tuning tables printed on the side) for a wide range of HF antennas. A TURF can actually also be used with the RT320 (coax connection from 320 TX O/P to TURF input) in place of the internal tuner, since the 320 tuner supports only wire antennas but the TURF has both wire and coax outputs.

There are two marks of the antenna base for coax and wire input intended for VHF and HF respectively - I have a couple and will check which is which in the morning.

Regards

Iain

Hi All

My name is Iain and my background is Amateur Radio and I have owned various ex-military sets since an R1155 in the 1980s - I now have a Clansman RT321/322 base station and a RT320 for portable use.

I have been a telecommunications engineer for most of my working life but I grew up on a farm in the far north of Scotland so 4WD and heavy vehicles are not new to me.

I am located in South Suffolk between Ipswich and Colchester.

I joined the forum because I am in the process of refurbishing a French Simca Marmon MH600 (SUMB) as a radio truck to allow me to take the RT322 into the field.

My radio and military vehicle web site is http://www.g0ozs.org/clansman and the SUMB pages will follow shortly ! In the meantime a gallery of the vehicle as I found it is at: http://http://www.g0ozs.org/marmon/2010-03/

Iain

73 de G0OZS